Wireless Location Assisted Zone Guidance System Incorporating Secure Transmission of Location

ABSTRACT

A fully self-contained portable location tracking device autonomously compares a current location with a latitude-longitude map stored in memory. The latitude-longitude map stores guidance zone values indicative of a predetermined safe zone, progressive alert zones, and a predetermined reference point. The guidance zone values represent actions to be taken based upon current location. When initiated by some combination of current location or zone value, location history, and time, or when otherwise queried, the tracking device transmits the offset from reference location, rather than actual current location data, to at least one wireless communications monitoring apparatus. When further security is desired, the transmitted offset is also digitally encrypted or otherwise obfuscated. The monitoring apparatus also stores a copy of the latitude-longitude map and reference point. Using the received offset, the monitoring apparatus knows both the location of the location tracking device and the actions to be taken based upon current location.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. provisional patentapplication 62/902,325 filed Sep. 18, 2019 of like title andinventorship, the teachings and entire contents which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

This invention pertains generally to electrical communications, and moreparticularly to condition responsive indicating systems with a wirelesscommunications link, at least one wireless communications monitoringapparatus, and at least one portable location tracking device. In onepreferred manifestation, a fully self-contained portable locationtracking device designed in accord with the teachings of the presentinvention monitors location relative to both of a predetermined area anda predetermined reference point, and securely communicates status to theat least one wireless communications monitoring apparatus.

2. Description of the Related Art

With the advent and substantial advancement of Global PositioningSystems (GPS), presently primarily used for navigation, artisans haverecognized the opportunity to incorporate GPS technology into personneltracking and pet containment. Several systems have been proposed in theliterature for several decades, but these systems have not as yetadvanced and been adopted to the degree that the literature proposes.

One significant limitation of prior art GPS systems is the accuracy ofthe system. Accuracy can be dependent upon variables such as atmosphericvariations, signal reflections and signal loss due to obstacles, andvariability intentionally introduced into the system. Similarvariability is found in various radio and cellular locating systems.

A GPS or similar navigation system that is accurate to plus or minus tenmeters is very adequate for navigational purposes, for example to guidea person to a commercial building for a meeting or for other commerce.However, this level of accuracy is completely unacceptable for petcontainment, personnel tracking, and machinery monitoring. For exemplarypurposes, many residential yards are forty feet wide, or approximately10 meters. A system that is only accurate to plus or minus ten metersmight try to indicate a portable location tracking device as being ineither neighbor's yard on any given day or at any given moment,depending upon unpredictable and uncontrollable variables such asatmospheric conditions. As will be readily appreciated, thisunpredictable locating will lead to incorrect actions and alerts, when,in fact, the portable location tracking device is within the properlocation. In turn, this will seriously erode confidence in the system,and can lead to very undesirable disregard for alerts issued by theapparatus.

Another limitation is the amount of calculation required to determinewhether the portable location tracking device is within a selected area.Most prior art GPS systems use nodes to define the perimeter, and thenmathematically calculate where the portable location tracking device isrelative to the nodes. Unfortunately, this requires a substantial amountof computation, which increases greatly as the number of nodes areincreased. As a result, these systems commonly rely upon a primaryprocessing system that is remote from the portable location trackingdevice, to which the portable location tracking device is coupled viaradio waves or the like. This permits the primary processing system toperform calculations and then relay results or control signals back tothe portable location tracking device. Undesirably, this also drainsprecious battery power, limiting usable time between battery rechargecycles, and again makes the portable location tracking device dependentupon real-time and continuous communication with a monitoring apparatus.In addition, the need for a secondary base station makes the system farless portable. For exemplary and non-limiting purpose, this means thattaking the portable location tracking device away from a home base to apark may be impractical or impossible.

A further limitation of the prior art is battery life. A portablelocation tracking device that must be removed and recharged every fewhours is unacceptable for most purposes. Unfortunately, the intensivecomputations required by prior art systems require either a fast andconsequently higher power processor unit, or a high power andessentially continuous communications link such as a radio link to abase station. While the portable location tracking device may transmitdata back to the base unit to avoid the need for battery-drainingcomplex computational ability, the apparatus still drains the batterydue to the high power required for real-time communications. To beeffective for real time behavioral modifications or positional controlfor moving beings and apparatus such as required in the training andmanagement of animals, the position must be recalculated veryfrequently, in some cases multiple times each second. As a result, ifthe base station is going to perform the calculations, then thesetransmissions must be occurring in real time at that same required rate.This means the communications with the base are commonly being repeatedin an almost non-stop and continuously exchanging stream. It will beapparent that walkie-talkies, cellular telephones, and other hand-heldradio devices all have very large batteries to provide adequatereal-time transmission and reception life, and yet these devices oftenonly support several hours of communications. As can be appreciated,size and weight are severely restricted for a small and portablelocation tracking device, and the inclusion of a large battery isundesirable.

An additional limitation of the prior art is the blocking or loss of thecommunications with a base unit. In the prior art, the portable trackingdevice is entirely dependent upon the base station to provide positioninformation. In the event the communication is lost or interrupted, theportable tracking device is rendered non-functional until communicationcan be restored.

Yet another limitation of the prior art is the unintentional blocking orloss of GPS signals. There are a number of conditions that can lead toloss of GPS signals. One is unfavorable weather, which can lead to aseverely attenuated satellite signal, and much higher Signal to NoiseRatios (SNR). Another condition is an adjacent building, canyon wall, orother obstacle that blocks satellite signals. Such a signal might, forexemplary purposes, either block all signals such as commonly occurswithin a building, or instead may only block signals from one direction.However, GPS systems require multiple satellites to obtain a positionfix, and even if only one of the satellites is blocked, then the abilityto accurately fix position may be lost. Another situation that can leadto signal loss is when the portable location tracking device itself iscovered. In such case, then satellite signals may either be blocked orbe too severely attenuated.

In any of these situations where the GPS signal is partially orcompletely blocked or attenuated, the latitudinal and longitudinalpositional accuracy will either be inadequate, or may be completelylost. In such instances, a prior art portable location tracking devicemay become completely non-functional. Worse, this loss of function canoccur without notice in an erratic manner, possibly causing severe harmor complete disruption or loss of the intended function.

The following patents and published patent applications are believed tobe exemplary of the most relevant prior art, and the teachings andcontents of each are incorporated herein by reference: U.S. Pat. No.4,393,448 by Dunn et al, entitled “Navigational plotting system”; U.S.Pat. No. 4,590,569 by Rogoff et al, entitled “Navigation systemincluding an integrated electronic chart display”; U.S. Pat. No.4,611,209 by Lemelson et al, entitled “Navigation warning system andmethod”; U.S. Pat. No. 4,817,000 by Eberhardt, entitled “Automaticguided vehicle system”; U.S. Pat. No. 4,999,782 by BeVan, entitled“Fixed curved path waypoint transition for aircraft”; U.S. Pat. No.5,067,441 by Weinstein, entitled “Electronic assembly for restrictinganimals to defined areas”; U.S. Pat. No. 5,191,341 by Gouard et al,entitled “System for sea navigation or traffic control/assistance”; U.S.Pat. No. 5,351,653 by Marischen et al, entitled “Animal training methodusing positive and negative audio stimuli”; U.S. Pat. No. 5,353,744 byCuster, entitled “Animal control apparatus”; U.S. Pat. No. 5,355,511 byHatano et al, entitled “Position monitoring for communicable anduncommunicable mobile stations”; U.S. Pat. No. 5,381,129 by Boardman,entitled “Wireless pet containment system”; U.S. Pat. No. 5,389,934 byKass, entitled “Portable locating system”; U.S. Pat. No. 5,408,956 byQuigley, entitled “Method and apparatus for controlling animals withelectronic fencing”; U.S. Pat. No. 5,450,329 by Tanner, entitled“Vehicle location method and system”; U.S. Pat. No. 5,568,119 bySchipper et al, entitled “Arrestee monitoring with variable siteboundaries”; U.S. Pat. No. 5,587,904 by Ben-Yair et al, entitled “Aircombat monitoring system and methods and apparatus useful therefor”;U.S. Pat. No. 5,594,425 by Ladner et al, entitled “Locator device”; U.S.Pat. No. 5,751,612 by Donovan et al, entitled “System and method foraccurate and efficient geodetic database retrieval”; U.S. Pat. No.5,791,294 by Manning, entitled “Position and physiological datamonitoring and control system for animal herding”; U.S. Pat. No.5,857,433 by Files, entitled “Animal training and tracking device havingglobal positioning satellite unit”; U.S. Pat. No. 5,868,100 by Marsh,entitled “Fenceless animal control system using GPS locationinformation”; U.S. Pat. No. 5,911,199 by Farkas et al, entitled“Pressure sensitive animal training device”; U.S. Pat. No. 5,949,350 byGirard et al, entitled “Location method and apparatus”; U.S. Pat. No.6,043,748 by Touchton et al, entitled “Satellite relay collar andprogrammable electronic boundary system for the containment of animals”;U.S. Pat. No. 6,114,957 by Westrick et al, entitled “Pet locatorsystem”; U.S. Pat. No. 6,172,640 by Durst et al, entitled “Pet locator”;U.S. Pat. No. 6,232,880 by Anderson et al, entitled “Animal controlsystem using global positioning and instrumental animal conditioning”;U.S. Pat. No. 6,232,916 by Grillo et al, entitled “GPS restraint systemand method for confining a subject within a defined area”; U.S. Pat. No.6,236,358 by Durst et al, entitled “Mobile object locator”; U.S. Pat.No. 6,263,836 by Hollis, entitled “Dog behavior monitoring and trainingapparatus”; U.S. Pat. No. 6,271,757 by Touchton et al, entitled“Satellite animal containment system with programmable Boundaries”; U.S.Pat. No. 6,313,791 by Klanke, entitled “Automotive GPS control system”;U.S. Pat. No. 6,421,001 by Durst et al, entitled “Object locator”; U.S.Pat. No. 6,441,778 by Durst et al, entitled “Pet locator”; U.S. Pat. No.6,480,147 by Durst et al, entitled “Portable position determiningdevice”; U.S. Pat. No. 6,487,992 by Hollis, entitled “Dog behaviormonitoring and training apparatus”; U.S. Pat. No. 6,518,919 by Durst etal, entitled “Mobile object locator”; U.S. Pat. No. 6,561,137 by Oakman,entitled “Portable electronic multi-sensory animal containment andtracking device”; U.S. Pat. No. 6,581,546 by Dalland et al, entitled“Animal containment system having a dynamically changing perimeter”;U.S. Pat. No. 6,700,492 by Touchton et al, entitled “Satellite animalcontainment system with programmable boundaries”; U.S. Pat. No.6,748,902 by Boesch et al, entitled “System and method for training ofanimals”; U.S. Pat. No. 6,903,682 by Maddox, entitled “DGPS animalcontainment system”; U.S. Pat. No. 6,923,146 by Kobitz et al, entitled“Method and apparatus for training and for constraining a subject to aspecific area”; U.S. Pat. No. 7,034,695 by Troxler, entitled “Large areaposition/proximity correction device with alarms using (D)GPStechnology”; U.S. Pat. No. 7,259,718 by Patterson et al, entitled“Apparatus and method for keeping pets in a defined boundary havingexclusion areas”; U.S. Pat. No. 7,328,671 by Kates, entitled “System andmethod for computer-controlled animal toy”; U.S. Pat. No. 7,677,204 byJames, entitled “Dog training device”; U.S. Pat. No. 8,155,871 by Lohiet al, entitled “Method, device, device arrangement and computer programfor tracking a moving object”; U.S. Pat. No. 8,115,642 by Thompson etal, entitled “Traveling invisible electronic containmentperimeter—method and apparatus”; U.S. Pat. No. 8,624,723 by Troxler,entitled “Position and proximity detection systems and methods”; U.S.Pat. No. 8,757,098 by So et al, entitled “Remote animal training systemusing voltage-to-frequency conversion”; U.S. Pat. No. 8,797,141 by Bestet al, entitled “Reverse RFID location system”; U.S. Pat. No. 8,839,744by Bianchi et al, entitled “Mobile telephone dog training tool andmethod”; U.S. Pat. No. 8,851,019 by Jesurum, entitled “Pet restraintsystem”; 2007/0204804 by Swanson et al, entitled “GPS pet containmentsystem and method”; 2008/0252527 by Garcia, entitled “Method andapparatus for acquiring local position and overlaying information”;2011/0193706 by Dickerson, entitled “Sensor collar system”; 2012/0000431by Khoshkish, entitled “Electronic pet containment system”; 2013/0127658by McFarland et al, entitled “Method and apparatus to determineactionable position and speed in GNSS applications”; and EP 0699330 andWO 94/27268 by Taylor, entitled “GPS Explorer”.

Other US patents and published applications, the teachings and contentwhich are incorporated herein by reference, include: U.S. Pat. No.4,967,696 by Tobias, entitled “Dog collar”; U.S. Pat. No. 5,046,453 byVinci, entitled “Animal Training Apparatus”; U.S. Pat. No. 5,491,486 byWelles et al, entitled “Mobile tracking units employing motion sensorsfor reducing power consumption therein”; U.S. Pat. No. 5,870,741 byKawabe et al, entitled “Information Management device”; U.S. Pat. No.6,079,367 by Stapelfeld et al, entitled “Animal training apparatus andmethod”; U.S. Pat. No. 6,415,742 by Lee et al, entitled “Dualtransmitter pet confinement and training system”; U.S. Pat. No.6,943,701 by Zeineh, entitled “Vehicular safety system and method”; U.S.Pat. No. 7,764,228 by Durst et al, entitled “Portable positiondetermining device”; U.S. Pat. No. 7,786,876 by Troxler, entitled “Largearea position/proximity correction device with alarms using (D)GPStechnology”; U.S. Pat. No. 7,856,947 by Giunta, entitled “Wirelessfencing system”; U.S. Pat. No. 7,920,066 by Troxler, entitled “Largearea position/proximity correction device with alarms using (D)GPStechnology”; U.S. Pat. No. 8,065,074 by Liccardo, entitled “Configurableinertial navigation system with dual extended kalman filter modes”; U.S.Pat. No. 8,149,110 by Troxler, entitled “Large area position/proximitycorrection device with alarms using (D)GPS technology”; U.S. Pat. No.8,155,871 by Lohi et al, entitled “Method, device, device arrangementand computer program for tracking a moving object”; U.S. Pat. No.8,955,462 by Golden, entitled “System and Method for Remote Guidance ofan Animal to and from a Target Destination”; U.S. Pat. No. 8,957,812 byHill et al, entitled “Position Tracking System and Method Using RadioSignals and Inertial Sensing”; U.S. Pat. No. 9,226,479 by Bianchi et al,entitled “Mobile telephone dog training tool and method”; 2001/0026240by Neher, entitled “Personal Locations Detection System”; 2004/0108939by Giunta, entitled “Wireless Fencing System with Tetherless Leash”;2003/0224772 by Patzer et al, entitled “Dynamic mobile stationconfiguration in wireless communications systems and methods therefor”;2004/0196182 by Unnold, Entitled “Intelligent Mobile Asset ManagementSystem”; 2005/0034683 by Giunta, entitled “Wireless Fencing System”;2005/0066912 by Korbitz et al, entitled “Method and Apparatus forTraining and for Constraining a subject to a specific area”;2006/0061469 by Jaeger et al, entitled “Positioning system that usessignals from a point source”; 2006/0197672 by Talamas et al, entitled“Virtual fence”; 2008/0036610 by Hokuf et al, entitled “Animal TrackingApparatus and Method”; 2008/0162034 by Breen, entitled “System andMethod for automatically generating sets of geo-fences”; 2008/0246656 byGhazarian, entitled “Automatic GPS tracking system with passive batterycircuitry”; 2009/0102668 by Thompson et al, entitled “Travelinginvisible electronic containment perimeter—method and apparatus”;2009/0267832 by Hymel, entitled “Systems and methods for dynamicallydetermining position”; 2009/0289844 by Palsgrove et al, entitled“Position monitoring system”; 2009/0292426 by Nelson et al, entitled“System and method for controlling a planter”; 2009/0325594 by Lan etal, entitled “Using base-station location to assist mobile-device systemacquisition”; 2010/0139576 by Kim et al, entitled “Electronic FenceSystem”; 2011/0163873 by McIntosh, entitled “Determination of time zoneand DST participation”; 2011/0172916 by Pakzad et al, entitled “mobiledevice positioning in a constrained environment”; 2011/0187537 byTouchton et al, entitled “Time of flight animal monitoring”;2012/0312250 by Jesurum, entitled “Pet Restraint System”; 2013/0008391by Berntsen, entitled “Method and system for fencing animals withoutusing a physical fence”; 2013/0141237 by Goetzl et al, entitled “dockingsystem and apparatus to track and stimulate an animal”; 2013/0157628 bykim et al, entitled “Smart phone based electronic fence system”;2013/0265165 by So, entitled “Position tracking apparatus for traininganimal”; 2013/0307688 by Hoffman et al, entitled “Personal security andtracking system”; 2013/0324166 by Mian et al, entitled “Method andapparatus using geofence to track individual group members”;2014/0230755 by Trenkle et al, entitled “Animal Indicator Apparatus”;2014/0251233 by Bianchi et al, entitled “Mobile telephone dog trainingtool and method”; 2015/0040839 by Goetzl et al, entitled “Integrated dogtracking and stimulus delivery system”; 2015/0016730 by Miller et al,entitled “Methods, apparatus, and articles of manufacture to measuregeographical features using an image of a geographical location”;2015/0020750 by Jesurum, entitled “Pet restraint System”; 2015/0107531by Golden, entitled “System and method for remote guidance of an animalto and from a target destination”; and 2016/0021849 by Loosveld,entitled “Method and system for localizing and displaying positions ofautonomously mobile objects”.

The present inventor has also previously developed various apparatus andmethods that have decreased computational requirements and RAM requiredsufficiently to provide a fully self-contained apparatus that may bothtrack location and take appropriate actions responsive to predeterminedzones stored within RAM. The apparatus and associated methods aredisclosed in U.S. Pat. No. 9,795,118 entitled “Wireless LocationAssisted Zone Guidance System”; U.S. Pat. No. 9,961,884 entitled“Wireless Location Assisted Zone Guidance System Compatible with Largeand Small Land Zones”; U.S. Pat. No. 10,064,390 entitled “WirelessLocation Assisted Zone Guidance System Incorporating a Multi-ZoneContainment Area”; U.S. Pat. No. 10,080,346 entitled “Wireless LocationAssisted Zone Guidance System”; U.S. Pat. No. 10,165,755 entitled“Wireless Location Assisted Zone Guidance System Region Lookup”; U.S.Pat. No. 10,165,756 entitled “Wireless Location Assisted Zone GuidanceSystem Incorporating a Rapid Collar Mount and Non-Necrotic Stimulation”;U.S. Pat. No. 10,172,325 entitled “Wireless Location Assisted ZoneGuidance System Incorporating Dynamically Variable Intervals BetweenSequential Position Requests”; U.S. Pat. No. 10,251,371 entitled“Wireless Location Assisted Zone Guidance System Incorporating a Systemand Apparatus for Predicting the Departure of an Animal From a Safe ZonePrior to the Animal Actually Departing”; U.S. Pat. No. 10,292,365entitled “Wireless Location Assisted Zone Guidance System IncorporatingShepherding of Wayward Dogs”; U.S. Pat. No. 10,342,218 entitled “GPS DogFence Incorporating Location Guidance and Positive ReinforcementTraining”; U.S. Pat. No. 10,405,520 entitled “Wireless Location AssistedZone Guidance System”; U.S. Pat. No. 10,455,810 entitled “WirelessLocation Assisted Zone Guidance System Region Lookup”; U.S. Pat. No.10,470,437 entitled “Wireless Location Assisted Zone Guidance System”;and U.S. Pat. No. 10,624,319 entitled “Wireless Location Assisted ZoneGuidance System Incorporating a Rapid Collar Mount and Non-NecroticStimulation”; US published applications 2015/0216142 entitled “WirelessLocation Assisted Zone Guidance System”; and 2019/0141953 entitled“Wireless Location Assisted Zone Guidance System IncorporatingDynamically Variable Intervals Between Sequential Position Requests”;and international published applications WO 2015/021116 entitled“Wireless Location Assisted Zone Guidance System”; WO 2019/182919entitled “Wireless Location Assisted Zone Guidance System IncorporatingSecure Transmission of Location”; WO 2020/142089 entitled “WirelessLocation Assisted Zone Guidance System Incorporating a Rapid CollarMount and Non-Necrotic Stimulation”; and WO 2020/145941 entitled“Wireless Location Assisted Zone Guidance System IncorporatingDynamically Variable Intervals Between Sequential Position Requests”;the relevant teachings and content of each which are incorporated hereinby reference.

While each of the foregoing patents and published applications haveoffered tangible features and benefits, there has continued to remain aneed for improved methods and apparatus to safely and securely monitorthe location of a portable location tracking device. Using theaforementioned technology, a parent is now able to track and monitor thelocation of a child, a friend can monitor and track the location ofanother friend, and an elderly patient with dementia can be tracked andmonitored, with the intent to keep them safe. These goals are of coursedesirable and highly beneficial.

However, with the introduction of the various location trackingapparatus has come a sometimes highly undesirable side effect. Not onlycan a parent track the location of the child, but so can a would-bekidnapper. A valuable package can be tracked not only by the owner, butalso by a thief. To reduce the chance for this corruption of anotherwise very beneficial set of tracking apparatuses, a system may beprovided with encryption. Unfortunately, not only has encryptionimproved, but so has the entire field of cryptography, includingdecryption. While an apparatus today maybe provided with an encryptioncode or apparatus that maybe difficult or time-consuming to break, inonly a matter of a few short months or years the hardware and softwareused for cryptography may advance sufficiently to render theseencryptions useless against even a poorly skilled hacker. Further, thisencryption and decryption requires processor intense operation, which asalready noted herein above is quite detrimental to both battery life andhardware costs.

As maybe apparent then, in spite of the enormous advancements andsubstantial research and development that has been conducted, therestill remains a need for an improved apparatus that operates in aself-sufficient manner, and that may further safely and securelycommunicate with a monitoring apparatus.

In addition to the foregoing documents, Webster's New UniversalUnabridged Dictionary, Second Edition copyright 1983, is incorporatedherein by reference in entirety for the definitions of words and termsused herein.

SUMMARY OF THE INVENTION

Exemplary embodiments of the present invention solve inadequacies of theprior art by providing a lookup table having a reference point. Thelookup table and reference point are incorporated into at least onemonitoring apparatus and at least one portable location tracking device.In a most preferred embodiment of the invention, the table is defined byrows and columns that are mapped to ordinate and abscissa data pointsrepresenting predefined geographic locations. Each data point offset inthe table corresponds to a predefined geographic offset, for example alatitude and longitude offset. Each datum point in the table stores avalue indicative of a particular one of several guidance zones. Eachguidance zone has an associated set of characteristics used to provideactions or lack thereof.

At the start of a tracking session, if the reference point is notalready predetermined, the reference point may be set for exemplarypurposes at the beginning of a tracking session by communication betweenthe monitoring apparatus and portable location tracking device. Thereference point will be a particular location within the map. Since mapsmay be custom, by the uniqueness of the map the reference point is thenalso custom. This means that the reference point is random and specificto the specific map, and not known to an unauthorized third party. Wherestock or widely available maps are used, a custom reference point mustbe determined to preserve the security of the present invention.

Once the tracking session begins, communication of current location fromthe portable location tracking device to the monitoring apparatus may beachieved by transmission of offset from the reference point. Since thereference point is only known by authorized devices, an unauthorizeddevice that intercepts the offset will be unable to determine an actualphysical location. As the portable location tracking device is movedabout, the determination of the guidance zone is made by determinationof the present location using GPS or equivalent signals. Identificationof the corresponding table location is made by calculating thelatitudinal and longitudinal offsets from the reference point, and usingthese offsets as the two indices for a double-indexed array. The valueretrieved from the double-indexed array identifies the guidance zone.Based upon either or both of portable location tracking device locationhistory and the guidance zone value returned from the table, a varietyof actions may be triggered within the portable location trackingdevice, such as providing appropriate stimuli, communicating a currentzone value, or communicating current offsets from the reference point.These same offsets from the reference location are what is transmitted,when so desired, to the monitoring apparatus, which may also thendetermine what guidance zone the portable location tracking device islocated within.

In a first manifestation, the invention is, in combination, a portablelocation tracking device and a monitoring apparatus. The portablelocation tracking device has a GPS location determination apparatusconfigured to determine an instantaneous latitude-longitude location ofthe portable location tracking device; memory containing atwo-dimensional data array corresponding to longitude and latitude; asecret reference point within the two-dimensional array that isprivately shared with the monitoring apparatus; and a data exchangeapparatus configured to transmit an offset between the instantaneouslatitude-longitude location of the portable location tracking device andthe secret reference point. The monitoring apparatus has: a dataexchange apparatus configured to receive the offset between theinstantaneous latitude-longitude location of the portable locationtracking device and the secret reference point from the portablelocation tracking device data exchange apparatus; and memory containinga two-dimensional data array corresponding to the portable locationtracking device two-dimensional array, and the privately sharedreference point within the monitoring apparatus two-dimensional arraycorresponding to the portable location tracking device secret referencepoint. The monitoring apparatus is configured to apply the receivedoffset between the instantaneous latitude-longitude location of theportable location tracking device and the secret reference point to theprivately shared reference point within the monitoring apparatustwo-dimensional array and thereby determine the instantaneouslatitude-longitude location of the portable location tracking device.

In a second manifestation, the invention is a method of securelytransmitting an instantaneous location of a portable location trackingdevice to a monitoring apparatus. According to the method, atwo-dimensional data array representing longitude and latitude isgenerated within each of the portable location tracking device and themonitoring apparatus. A privately held reference point within thegenerated two-dimensional data array is stored into each of the portablelocation tracking device and the monitoring apparatus. An offset betweena data table representation of an instantaneous location of a portablelocation tracking device and the privately held reference point istransmitted to the monitoring apparatus. The transmitted offset isapplied to the monitoring apparatus two-dimensional data array referencepoint to locate the data table representation of an instantaneouslocation of the portable location tracking device.

OBJECTS OF THE INVENTION

The present invention and the preferred and alternative embodiments havebeen developed with a number of objectives in mind. While not all ofthese objectives are found in every embodiment, these objectivesnevertheless provide a sense of the general intent and the many possiblebenefits that are available from embodiments of the present invention.

A first object of the invention is to provide a safe and secureapparatus for monitoring the location of a portable location trackingdevice. From the descriptions provided herein and the teachingsincorporated by reference herein above, it will be apparent that thepresent invention may be applied in certain instances to humans,livestock, pets, wild game, or other animals, machinery, and otherdiverse apparatus. A second object of the invention is to provide afully self-contained apparatus that will determine location and takevarious appropriate actions or inactions based upon that location forextended periods of operation. As a corollary, the fully self-containedportable location tracking device is preferably operational withuniversally available location systems, including but not limited tosatellite GPS, cellular telephone triangulation systems, and radiotriangulation system such as Loran, but may alternatively be providedwith a custom location system if so desired. By using universallyavailable location systems, there is no limit on the locations where theapparatus may be used. Another object of the present invention is toenable simple and efficient set-up and operation by a person. A furtherobject of the invention is to efficiently and expeditiously apply aportable location tracking device to a subject to be tracked, whetherthe subject is animate or inanimate, with minimal training time andknowledge required for proper and effective use of the apparatus. Yetanother object of the present invention is to enable the establishmentof an acceptable area or “safe zone” which may have very complexgeometry using only the self-contained portable location trackingdevice, and to adjust or redefine the area again by simple manipulationof the self-contained portable location tracking device. An additionalobject of the invention is to enable the self-contained portablelocation tracking device to automatically generate a number of zonesthat facilitate desired use and generation of action, including when sodesired a set of progressive zones that may share a common action thatescalates as the zones are progressively penetrated. An even furtherobject of the invention is to facilitate very secure and very low-powercommunication from a portable location tracking device to a monitoringapparatus on an “as-needed” basis that may for exemplary andnon-limiting purpose include one of status, current zone, or offset froma reference point. As a corollary thereto, transmissions from theportable location tracking device are preferably brief, normallyinfrequent, and encoded in such a way as to foil cryptographic decodingand decryption.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, advantages, and novel features of thepresent invention can be understood and appreciated by reference to thefollowing detailed description of the invention, taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 illustrates a map of numerical values visually overlaid onto andelectronically associated with an exemplary property such as might bemapped in accord with the teachings of the present invention.

FIG. 2 illustrates alternative reference points and exemplary movementof a preferred embodiment self-contained portable location trackingdevice about the exemplary property of FIG. 1 as represented on the mapof numerical values of FIG. 2.

FIG. 3 illustrates the preferred embodiment self-contained portablelocation tracking device in further combination with a plurality ofsatellites and a wireless communications monitoring apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Manifested in the preferred embodiment, the present invention providescommunication of current location from a portable location trackingdevice to a monitoring apparatus by transmission of offset from apreviously communicated and securely shared reference point.

In a preferred embodiment wireless location assisted zone guidancesystem 100 designed in accord with the teachings of the presentinvention, a person might want to monitor a child, pet, wild game,machine, or other animate or inanimate object located within an exampleproperty 1 such as that illustrated in FIG. 1. An outer limit of theproperty 2 may encompass one or more buildings 3, a driveway 4, and amailbox 5. For exemplary purposes, a mailbox may be located on a smallpeninsula 6 which could extend beyond the bounds of the particularproperty location.

A self-contained portable location tracking device 120, which might forexemplary purposes and not solely limiting thereto resemble thatillustrated in FIG. 3, will preferably contain the necessary electroniccomponents to perform a number of tasks as described herein. Someexemplary components include: components to receive and decipherlocation determining signals through GPS location determinationapparatus 121; a microprocessor, programmable logic controller, or anyother equivalent or suitable apparatus 123; a data exchange apparatus125 which might comprise a radio or other communications hardware; andalso preferably both volatile and non-volatile memory such as RAM 127and non-volatile storage 129.

In the preferred embodiment wireless location assisted zone guidancesystem 100 as illustrated in FIG. 3, a plurality of satellites 110transmit GPS signals, which may then be received and converted tolatitude and longitude references by the GPS location determinationapparatus 121. These latitude and longitude references are thencommunicated from GPS location determination apparatus 121 tomicroprocessor 123. While latitude and longitude references arepreferred, in alternative embodiments any suitable coordinate referencerepresentative of a geographic area may be used.

A new area may be established such as described in greater detail in myU.S. Pat. No. 9,795,118 and published application 2015/0216142incorporated herein above by reference, or by any other suitabletechnique. In one embodiment described therein, outer limit 2 istraversed, while the GPS location determination apparatus 121 andmicroprocessor 123 track these locations and store them in either orboth of RAM 127 and non-volatile storage 129. In an alternativeembodiment, maps created upon or stored within various computing devicesmay be transferred through data exchange 125 and microprocessor 123 toeither or both of RAM 127 and non-volatile storage 129.

Next, microprocessor 123 or other suitable processor will preferablyautomatically convert this outer limit 2 into a table 10 of values suchas illustrated for exemplary purposes in FIG. 1. The embodimentsdisclosed herein maybe implemented with a general purpose processor, adigital signal processor (DSP), an application specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices.

While the numerals 0-3 illustrated in table 10 are used therein for thepurposes of the present illustration, any suitable designations, whethernumeric or not, may be used. As but one example, the numerals 0-3represent four choices, and so may easily be represented by two bits ofdata. In such case, the possible combinations are binary 00, 01, 10, and11. Furthermore, the present invention is not limited solely to fourchoices, and any number of choices, including both more and fewer thanfour, determined by a designer to be appropriate for the apparatus thatis otherwise generally compliant with the remainder of the presentdescription will be understood to be incorporated herein.

While FIG. 1 illustrates an exemplary outline of an area, which is asubset of the total property, the area can be of any geometry, and inthe example is somewhat irregular.

In the preferred embodiment wireless location assisted zone guidancesystem 100, a number of different zones are defined based upon thetraversal of outer limit 2 during initial setup. The area beyond outerlimit 2 is defined by an “out-of-bounds” zone 11 represented by anumerical value of zero at each discrete data table location Immediatelyinside of the zero-value locations is a zone of locations assigned anumerical value of one. This will be referred to herein as the “secondalert zone” 12. Between “out-of-bounds” zone 11 and “second alert zone”12 in FIG. 1, a dashed line 13 has been drawn for illustrative purposes.This line does not actually exist in stored data table 10, but insteadhelps to better illustrate the various zones that are defined by thevarious location values.

A plurality of discrete locations relatively inward from the secondalert zone 12 are assigned a numerical value of two, and represent a“first alert zone” 14. Again, for the purpose of illustration only, adashed line 15 is shown separating first alert zone 14 from second alertzone 12. Again, and like line 13, this line 15 does not actually existin the stored data table, and is provided solely for illustrativepurposes.

Finally, an innermost “safe zone” 16 preferably intentionallyencompasses the largest area of all zones and is populated with discretelocation values assigned to equal the numerical value of three. Dashedline 17, like lines 13 and 15, indicates the separate zones, but doesnot exist in the stored data table.

As is evident when reviewing FIG. 1, line 13 corresponds approximatelyto outer limit 2 and so is shared by both reference numerals. Due to thediscrete nature of the resolution of the particular position determiningsystem, such as a GPS system in preferred embodiment wireless locationassisted zone guidance system 100, the points defined during thetraversal of outer limit 2 may or may not exactly correspond to the landlocation. In addition, since outer limit 2 may not be linear, and mayinstead include a number of irregularities such as peninsula 21 andslightly cropped corners 23 and 26 referenced in FIG. 2, the data pointsmore interior but generally adjacent to these irregularities will havevariability in their associated geometries relative to that of the outerlimit 2. So, and again for exemplary purposes, peninsula 21 is toonarrow to provide for the as-illustrated exemplary two data point widthprovided for each zone. Nevertheless, there is a single data point ofnumerical value 2 protruding at reference numeral 22 illustrated in FIG.2. Consequently, as outer limit 2 was traversed at set-up, aself-contained portable location tracking device 120 may reach the baseof mail box 5, which is located at this single data point of numericalvalue 2 at reference numeral 22, without passing into the second alertzone. Nevertheless, the self-contained portable location tracking device120 will still pass into the first alert zone, and an action associatedwith the first alert zone will be initiated and carried out. Similarly,the intricacies of notched corner 26 are lost as the corner becomes asimple square corner at reference numeral 27 of FIG. 2. Likewise, theelaborate stepping of cropped corner 23 fades some to simpler corner 24,and becomes a very simple single curve at more interior corner 25.

Also strictly for the purpose of illustration, and not limiting theinvention solely thereto, two GPS location points are used as the widthof each of the first alert and second alert zones. Consequently, in theembodiment as illustrated, each of these first alert and second alertzones are calculated to be approximately two GPS points in width. Itwill be understood herein that the width of the alert zones may bepredetermined to be more or less than the exemplary and illustrated twodata points. Furthermore, the number of alert zones may be varied fromthe two zones that are illustrated.

While the alert zone areas are, in fact, two data points wide, the widthof the alert zones at sharp transition points, such as corners, may begreater or less than two data points in width. The particular decisionsfor how to shape interior zones will be determined by algorithms chosenor written by a designer at design time. Furthermore, there may be timeswhere assisted guidance zones may take on a very irregular shape. Thiscan occur, for exemplary purposes, when there is a narrow peninsulabetween two larger safe zones. When there is not sufficient room for thepredetermined number of alert zone location points, such as withinpeninsula 21 of FIG. 1, in the preferred embodiment the data pointcalculations still begin with the second alert zone value adjacent tothe “out of bounds” area. This presents consistent operation near theborders, and provides more consistent system behavior, which in somecases may be very important.

As may be apparent, a person may choose where to traverse in order tocontrol the formation of various zones. As an example, a person tryingto create a larger buffer adjacent a high traffic road would, whensetting up the zones, simply walk an outer limit farther from the edgeof the road. This maintains more consistent alert zone widths, which isbelieved to offer better communication and training for animate beingsthan varying the width of the alert zones. Nevertheless, andalternatively, it is contemplated herein to allow a person, the system,or self-contained portable location tracking device 120 to vary thewidth of alert zones to correspond with various objects or hazards suchas fences, gardens, and roadways.

FIG. 2 illustrates the data table 10 representation of the land area ofFIG. 1, but without the land features shown. In accord with the presentinvention, a latitude and longitude land map is converted to and savedas an X-Y plot or table of points, where one axis (in this case therows, also referred to as the abscissa) represents latitude and theother axis (in this case as illustrated, the columns, also referred toas the ordinate) represents longitude. Each point is then assigned anumerical value that is representative of a zone within the assistedguidance region.

These points may for exemplary purposes and in accord with the preferredembodiment, correspond to specific points of geographic latitude andlongitude determined to a particular degree of resolution. The degree ofresolution may typically be the limit of precision available for aparticular location system, such as six decimals of precision in a GPSsystem. So, as represented in FIG. 2, the latitude and longituderepresentations are presented to six decimal precision, though othersuitable levels of precision are considered incorporated herein.

Noteworthy herein is the fact that the data points do not correspond toan exact measure in feet or inches. Instead, and as known in theindustry of mapping, a single second of longitude at the equator is theequivalent of approximately 101 feet. In contrast, a single second oflongitude at sixty degrees north latitude, which is approximately thelocation of Oslo, Norway; Helsinki, Finland; and Anchorage, Ak.; is onlyapproximately 51 feet. Taken to the extreme, at the north and southpoles, a second of longitude is zero feet. For prior art systemsattempting to calculate distances in feet or inches, this deviation oflongitudinal distance as the collar moves away from the equatordrastically increases the complexity of calculations required. Incontrast, the present invention directly associates GPS data points withzones, and disregards the distance in feet or inches that this may beequivalent to.

Storage of data table 10 requires memory, and a suitable electronicsystem within self-contained portable location tracking device 120 willnot be provided with unlimited memory within which to store data points.The particular type of memory selected is well within the level of skillof a designer of portable devices using micro-processors,micro-controllers and the like, and the invention is not limited to asingle or particular type of memory. In accord with a preferredembodiment of the system, the memory will be divided into somecombination of slower non-volatile storage 129 and relatively faster butvolatile RAM 127. The slower, non-volatile memory for exemplary butnon-limiting purposes might comprise well-known flash memory.

A reference location within table 10 will be determined. This referencelocation may be any position within the table. For exemplary andnon-limiting purposes, a reference location will be selected from thecentroid 44 of the intended safe zone as labeled in FIG. 2, the minimumlatitude and longitude of the zone or data table, or even some otherlocation entirely. For the purposes of illustrating the presentpreferred embodiment wireless location assisted zone guidance system100, the lower-left corner may be understood to be the referencelocation, identified as reference point 42 in the illustration of FIG.2.

The data table 10 populated with zone values as illustrated in FIGS. 1and 2 needs to be stored within both self-contained portable locationtracking device 120 and monitoring apparatus 130. This may be achievedthrough any suitable communication, such as through a communicationinvoked between tracking device data exchange 125 and monitoringapparatus data exchange 135. While any means of communication may beinvoked, alternatives to unencrypted wide area radio communications arepreferred for enhanced security.

For exemplary and non-limiting purpose, one approach is the use ofencryption techniques, for exemplary and non-limiting purposes such asare common in Internet and data communications today. One such knownstandard is the Transport Layer Security (TLS) encryption, though thereare many other standards and techniques. In some embodiments, a secureserver invoking TLS encryption may store one or more maps, and may beaccessed by both self-contained portable location tracking device 120and monitoring apparatus 130.

Another approach is the use of a local communications channel. Again forexemplary and non-limiting purpose, Near Field Communication (NFC),direct wired connection, or other alternative communications channel maybe used to provide an initiation of both devices 120, 130, such as atransfer of the reference point and map of zones.

Noteworthy is the fact that many of these communications techniques arenot mutually exclusive. In consideration thereof, they may be combinedfor further security enhancement. Consequently, and again for exemplaryand non-limiting purpose, in some embodiments the data transmittedduring an NFC exchange will be further encrypted so that even if anotherdevice is close enough in proximity to detect the NFC exchange, the datawill still be unuseable without decryption.

By invoking this initial transfer using an alternative mode ofcommunication, particularly one such as the direct wired connection orNFC that is much less susceptible to being externally hacked, a thirdparty will not have access to data table 10 or a reference point such aseither of the safe zone centroid 44 or reference point 42.

In some embodiments, the reference point is randomly or pseudo-randomlygenerated by one or the other of the devices 120, 130 during theexchange therebetween, rather than having been stored on either devicebeforehand. In addition, where multiple devices within a single guidanceregion may be monitored by one monitoring apparatus 130, in someembodiments it is preferable to use a random or pseudo-random generatorwith the generation of reference point for each self-contained portablelocation tracking device 120. In this case, a security breach of oneself-contained portable location tracking device 120 will not enable ahacker to access the location of any other self-contained portablelocation tracking device 120.

In some embodiments, in addition to exchanging the reference pointbetween self-contained portable location tracking device 120 andmonitoring apparatus 130, a pre-shared key will also be exchanged. Thiskey can then be used as known in the field of cryptography to facilitateencryption of the offset from reference.

Once data table 10 and a suitable reference point such as referencepoint 42 have been shared between self-contained portable locationtracking device 120 and monitoring apparatus 130, or otherwiseestablished, preferred embodiment wireless location assisted zoneguidance system 100 can begin operation.

When operational, self-contained portable location tracking device 120will receive GPS signal transmissions from a plurality of satellites110, typically three or more satellites. The received signals areconverted by GPS location determination apparatus 121 into latitude andlongitude references, which are then forwarded to and received bymicroprocessor 123. Microprocessor 123 will use the current latitude andlongitude signal forwarded from GPS location determination apparatus 121to find the location within data table 10 corresponding to the currentlocation.

The offset determination may be as simple as a simple subtraction of thereference location, such as reference point 42 of FIG. 2, from thecurrently determined location. Then, this difference is used as thetable index, to directly address the particular table location. In thepreferred embodiment, each data point is stored in memory using adouble-indexed array, with each of the two indices of the array uniquelyrepresenting one of the latitudinal or longitudinal offset from thereference point. For exemplary purposes, this may be written asArrayName[latitude-offset][longitude-offset]. Each unique[latitude-offset][longitude-offset] may for exemplary purposes point toa unique location in memory where the zone value associated with thatgeographic location is stored.

In an alternative embodiment, the offset may be additionally convertedin a proportional or scalar calculation, where a particular number ofdegrees of latitude, for example, are known to equal one data pointshift to the right in table 10. This requires storing the scalarconversion and an extra scalar calculation to look up the data value fora location, both which may be undesirable for some applications.

Once the offset is calculated, then microprocessor 123 will query thememory location and the contents of the memory are returned. Forexemplary and non-limiting purpose, the contents may be in the form of anumerical value from 0-3, the meaning which represents whether theself-contained portable location tracking device 120 is comfortablywithin the safe zone (“3” in the preferred embodiment), or is in thefirst alert (“2” in the preferred embodiment), second alert (“1” in thepreferred embodiment), or out-of-bounds zones. After GPS location isdetermined, the only calculation required during operation ofself-contained portable location tracking device 120 to determinewhether device 120 is within an assisted guidance zone is thecalculation of offset in latitude and longitude from the referencepoint, such as reference point 42 in the lower left corner of table 10.This is a very rapid and easy calculation, followed by anear-instantaneous read of the memory contents. In the preferredembodiment wireless location assisted zone guidance system 100 then, allnumerical representation calculations are performed at the time theouter limit is defined, and then these numerical representation tilesare saved, preferably in non-volatile storage 129 such as within EEPROM,flash memory, or equivalent storage. Saving in non-volatile storage 129allows the stored map to be used at a later date, even if the batteryshould fail in the interim.

The procedure used to clear a map from non-volatile storage 129 is alsoquite simple in the preferred embodiment. Once the user selects todelete the map, the associated memory locations are simply rewritten tonumerical values of zero; or simply deleted from a directory of memoryor a file allocation table; or otherwise deleted as known in the fieldof computing.

When more than one map is desired to be saved, the data tablescontaining zone values may be swapped into and out of active memory asrequired. This means that storage of diverse locations does not requirestorage of every location in between. So, for example, storage of twodistinct one acre maps on opposite sides of the earth does not requirestoring millions of acres of maps. Instead, only the data tableassociated with a latitude and longitude actually needed is required tobe stored in memory. While the use of these smaller data tables is notessential to the operation of the present invention, the ability tocreate these means that with only very modest amounts of memory andprocessing capability, the present invention may be used to map one or aplurality of assisted guidance regions literally anywhere on earth.

Using the teachings of the present invention, the self-containedportable location tracking device 120 may be designed to contain anentire and independent wireless location assisted zone guidance system.In other words, no additional components would need to be purchased oracquired, nor is there a need for any other external device other thanthe plurality of GPS satellites 110. Self-contained portable locationtracking device 120 will preferably interact directly with GPS signalsreceived from GPS satellites 110, and may for enablement use acommercially available set of components to determine latitude andlongitude.

A number of other features may also desirably or optionally beincorporated into a preferred embodiment wireless location assisted zoneguidance system 100. Some of these are described and set forth in my USpatents and published applications incorporated herein above byreference.

In addition, in accord with the present preferred embodiment wirelesslocation assisted zone guidance system 100, a monitoring apparatus 130will also be provided. Monitoring apparatus 130 in preferred embodimentwireless location assisted zone guidance system 100 may for exemplaryand non-limiting purpose have a GPS location determination apparatus131; a microprocessor 133; a data exchange apparatus 135; RAM 137; andnon-volatile storage 139. GPS location determination apparatus 131 isoptional and not required for the operation of self-contained portablelocation tracking device 120, but may offer benefit in some situations,such as the physical tracking of self-contained portable locationtracking device 120 with a portable monitoring apparatus 130.

As noted herein above, the provision of data exchange apparatuses 125,135 allows assisted guidance region maps and reference point to becommunicated from an external computing device. This may be from anotherself-contained portable location tracking device 120, a monitoringapparatus 130, or from a cellular telephone or various other mobile orfixed computing devices. To facilitate such transfer, self-containedportable location tracking device 120 and monitoring apparatus 130 willpreferably be provided with a local interface, such as through dataexchange apparatus 125, 135. The local interface may be of any suitabletype, including but not limited to wireless Bluetooth™, NFC, cellular,or other type of radio or alternative communications link, or wiredcommunications channel.

Once a reference point and data table have been transferred between orto both of self-contained portable location tracking device 120 andmonitoring apparatus 130, the only data required to be transferred froma self-contained portable location tracking device 120 to a wirelesscommunications monitoring apparatus 130 is the number of map pointsoffset from the reference point that represents the current location ofportable location tracking device 120. In other words, if the portablelocation tracking device is at position 41 in FIG. 2, this location isoffset from reference point 42 by three points along the X-axis orabscissa, and six points along the Y-axis or ordinate. Portable locationtracking device 120 may simply transmit the offset from reference as thetwo integers “3” and “6” sequentially. Upon receipt of “3 6”, wirelesscommunications monitoring apparatus 130 through microprocessor 133 willcalculate the “3 6” offsets using data table 10 to determine the exactlocation of portable location tracking device 120, and can additionallyimmediately assess that self-contained portable location tracking device120 is located in the first alert zone. If this location is intended toinitiate some action, event, or sequence of events within wirelesscommunications monitoring apparatus 130, then through control ofmicroprocessor 133 such action, event, or sequence will be initiated. Asa further example, position 43 might be represented by offsets of fourand three, or simply “4 3”.

As portable location tracking device 120 moves from location tolocation, GPS location determination 121 continues to provide locationinformation to microprocessor 123. As a result, portable locationtracking device 120 is location-aware, and with changes in either timeor location, portable location tracking device 120 will autonomouslycheck the onboard map to determine a zone value, and act, if needed.

Since status processing happens locally within portable locationtracking device 120, the device only needs to communicate when there isa problem or action required at monitoring apparatus 130, to giveinfrequent time-interval based updates to confirm proper operation andsignal lack of problem or action required, or to reply to a request forposition from monitoring apparatus 130. In addition, there may be timeswhere an action is initiated by some combination of current location,location history, and time.

The transmission by portable location tracking device 120 may simply bea signal representative of the two offset numbers. There are severalbenefits to this extremely compact transmission of the two numbers,including battery preservation and location security.

A short and compact transmission requires very little power, sobatteries will last longer. This is very complementary to the portablelocation tracking device 120 being autonomous and location aware, and soalso requiring very few transmissions. This combination of few andcompact transmissions provides very little drain on batteries.

Another benefit of the compact transmission of the two offset numbers isthat a third party receiving the transmission will not have enoughinformation to reveal the location of the portable tracking devicewithout also knowing the reference point. Therefore, location securityis preserved even if third parties may intercept the transmission fromportable location tracking device 120. In addition, a short and compacttransmission is also much more difficult to locate through triangulationor other technique, meaning the location of portable location trackingdevice 120 is extremely difficult to discern by untrustworthy thirdparties. Therefore, a short “burst” transmission at infrequent intervalsboth improves battery life and greatly enhances security of preferredembodiment wireless location assisted zone guidance system 100.

As already described, the transmission may simply be the data offset.However, there are several techniques that in some embodiments of thepresent invention will provide even greater security. As noted hereinabove, the data being transmitted may be encrypted data. Consequently,the “3 6” transmission may be encrypted, such as with the encryption keyexchanged with the initiation between self-contained portable locationtracking device 120 and monitoring apparatus 130. In furtherembodiments, the data transmission may also include new encryption keys,resulting in an ever-changing encryption.

In other embodiments, the offset may be calculated not only as theoffset from the reference point, but additionally adjusted using apseudo-random generator. If these offsets are altered in a known way,such as being further offset by a pseudo-random number generator thatcan be sequenced identically at both self-contained portable locationtracking device 120 and monitoring apparatus 130, then monitoringapparatus 130 can subtract out the pseudo-random offset to therebycalculate the actual or real offset value detected by self-containedportable location tracking device 120.

Encrypting the offset from reference using a cryptography key requiresgreater calculation and associated battery consumption, but thepseudo-random generated offset provides enhanced security. As a result,encryption established at initiation between self-contained portablelocation tracking device 120 and monitoring apparatus 130 or laterthrough encryption keys being exchanged at one or more communicationstherebetween can even eliminate sophisticated attempts to hack thelocation of a self-contained portable location tracking device 120.

As described above, in an alternative embodiment, the offset may beadditionally converted in a proportional or scalar calculation, where aparticular number of degrees of latitude, for example, are known toequal one data point shift to the right in table 10. This requiresstoring the scalar conversion and an extra scalar calculation to look upthe data value for a location. In a further alternative embodiment ofthe present invention, this scale factor can be leveraged to improvesecurity and battery life further.

In this embodiment, the scale factor is transferred between or to eachself-contained portable location tracking device 120 and monitoringapparatus 130 at or about the same time as the data table 10 andreference point are provided. This scale factor will further obfuscatethe location of portable location tracking device 120. For exemplarypurposes, if the scale factor is 16, the accuracy of the location wouldbe about 1 meter at 45 degrees in latitude. However, if the scale factoris higher, then the accuracy would be lower. This has two benefits.First, a third party recipient of the transmitted offset would have noidea what the scale factor would be, so even if they knew the pre-sharedreference location, they still would not know the actual location of theperson. Secondly, as the scale factor increases, the amount of times aportable location tracking device 120 would need to transmit goes down,which saves on battery.

While the two number (Lat-Lon offset) transmission described hereinabove is most compact, sending the two offsets in sequence and withoutany separator risks confusion. For example, if there are a total ofthree digits transmitted there is uncertainty whether the middle digitmight apply to latitude offset or to longitude offset. Consequently,there will preferably be either a short time gap in the transmission orother predetermined separator signal or character between the twooffsets. In addition, a predetermined “finished” or “end oftransmission” signal can avoid the risk of misinterpretation of the dataif a signal were lost or truncated before complete transmission.

In some embodiments, the separator characters are randomly generatednoise, but are located in predetermined positions with predeterminedlength. For exemplary and non-limiting purpose using position 41 in FIG.2, having a location offset from reference point 42 by three pointsalong the X-axis or abscissa, and six points along the Y-axis orordinate, the previously described transmission would be “3 6”. Againfor exemplary and non-limiting purposes, by assigning the first, third,and fifth characters as noise values, the transmission might then be“N3N6N”, where “N” represents a randomly generated noise character.Again as just a single example, a literal conversion of the “3 6”position 41 could be “$3J69”. The monitoring apparatus 130 knows tostrip the first, third, and fifth characters, once again revealing “36”. However, to a third party, the string of data “$3J69” appears to bean encrypted string such as would be created by the earlier embodimentdescribed above using TLS or other encryption. Yet, should the thirdparty hacker try, the string will not be decrypted using any key.

In other embodiments, additional characters may be inserted using apseudo-random generator. In such case, and as long as self-containedportable location tracking device 120 and monitoring apparatus 130 areboth provisioned with like generators, even positions of noisecharacters, or alternatively position data characters, in someembodiments and lengths of noise characters in some embodiments maybevaried as controlled by the pseudo-random generator. Once again, thetransmitted data will visually appear to be a string of unintelligiblecharacters without knowledge of the reference point and pseudo-randomgenerator.

In yet other embodiments, the reference point itself is changedaccording to a reproducible pattern, such as a predetermined sequence oragain a sequence of pseudo-randomly selected locations within the datatable. Again for exemplary and non-limiting example, the reference pointat a first transmission is point 42 in FIG. 2. In such case, ifself-contained portable location tracking device 120 is at point 41, thetransmission as noted above is “3 6”. If there is predeterminedagreement for rolling reference points, a second transmission might usepoint 43 of FIG. 2 as the reference point.

In such case, and with no change in position of self-contained portablelocation tracking device 120, meaning it remains at point 41, the offsettransmitted by the second transmission would be “−1 2”.

It is appropriate to note that in any embodiments where pseudo-randomgenerators or rolling references are used, each transmission eitherrequires confirmation of receipt from monitoring apparatus 130 bereturned to self-contained portable location tracking device 120, orthere must be transmitted an identifier of the number of thetransmission. Otherwise, even if only one transmission is dropped fromself-contained portable location tracking device 120 to monitoringapparatus 130, any further data received by monitoring apparatus 130would truly be unintelligible.

In yet other embodiments, two-factor authentication betweenself-contained portable location tracking device 120 and monitoringapparatus 130 may be used to relocate the reference point.

Each of these embodiments that alter the transmission of offset from thebasic “3 6” approach share a common overriding characteristic. Eachapproach starts with an already cryptic reference point offset, the “36”, and adds to that various forms of noise that further obfuscate thecontent.

While encryption-decryption algorithms, pseudo-random sequences, randomor pseudo-random data fill, moving reference points, and rolling codesare described herein above, those skilled in the art will recognize thatany suitable obfuscation or encryption technique may be added to thealready cryptic reference point offset data. When executed well,interception of the signal will only yield what appears to be noise, andeven after passing the data through any single conversion or decryptiontechnique, will still yield what appears to be noise. Those familiarwith obfuscation or encryption techniques may in some embodimentsgenerate well-distributed noise within or in combination with the data,yielding a resulting transmission resembling Gaussian noise.

In situations where there may be more than one portable locationtracking device 120 operating within an allocated communicationschannel, and where these tracking devices may potentially overlap inlocation, a “station identifier” that is unique to each portablelocation tracking device 120 will also preferably be transmitted. Thisavoids confusion over which portable location tracking device 120 istransmitting. However, in those embodiments where either thecommunications channels can be kept separate, or the locations of theportable location tracking devices 120 will be unique to a particulardevice and not be shared by two devices, then the station identifierwill not be required.

In preferred embodiment wireless location assisted zone guidance system100, the signals are transmitted uni-directionally from portablelocation tracking device 120 to any device equipped to receive thesignal. As described herein above, this preserves a short transmissionburst, and improves security of the system.

Nevertheless, in alternative embodiments, a bi-directional transmissionmay be desired or required. When so desired, an acknowledgment or thelike may be transmitted from wireless communications monitoringapparatus 130 to portable location tracking device 120 to confirmreceipt of a complete transmission. In addition, bidirectionalcommunications enable monitoring apparatus 130 to query portablelocation tracking device 120 of status or location when so desired. Formany applications, this ability to query may be highly desirable.

However, any benefits of bidirectional communication must still beweighed against potential loss of security. One attack vector is“pinging” portable location tracking device 120, to cause repeatedtransmissions that can be used to triangulate the location of portablelocation tracking device 120. The risk of this type of attack in someembodiments of the present invention is mitigated by limiting how oftenportable location tracking device 120 is allowed to respond to suchqueries through limits that may for exemplary and non-limiting purposebe set in software and enforced by microprocessor 123. In addition, in abidirectional communications implementation of preferred embodimentwireless location assisted zone guidance system 100, there will mostpreferably be provided further encryption or “station identification”,in some embodiments with further password or key validation or otherknown security techniques, making it much more difficult andtime-consuming for adversarial access and location determination.

As aforementioned, there will preferably be multiple zones in theassisted guidance region. For exemplary and non-limiting purposes, inpreferred embodiment wireless location assisted zone guidance system 100these are illustrated in FIGS. 1 and 2 as the “safe”, “first alert”,“second alert”, and “out-of-bounds” or “outside” zones, though there maybe more or fewer zones, and alternative titles may be used to providebetter description for a particular intended application of preferredembodiment wireless location assisted zone guidance system 100. Each ofthese zones maybe used to initiate a particular action, sequence, orlack thereof.

There are many potential applications for a wireless location assistedzone guidance system designed in accord with the teachings of theinvention. For exemplary and non-limiting purposes, in one embodiment awearable “safe zone” alerting system monitors children and vulnerableadults. In a manner similar to that already described herein above withregard to the property of FIG. 1, and as illustrated for exemplarypurpose also in FIG. 2, a region is identified, and then one or moreprogressive alert zones are established during the construction of adata table such as data table 10. The resulting data table and apre-defined reference point are communicated to at least oneself-contained portable location tracking device 120 and at least onemonitoring apparatus 130. As also described herein above, self-containedportable location tracking device 120 is capable of fully autonomousoperation. As a result, no communications are required while themonitored person moves about in the safe zone. This is illustrated inFIG. 2 as movement from location A to location B. No transmissions areinitiated, and battery power is preserved. When desired, and ifbidirectional communications are provided, monitoring apparatus 130 mayalso query the location of the person when needed or desired.

Continuing the exemplary cases of application to personal safety ofchildren or the elderly, if the monitored person leaves the an areadefined by data table 10 as being safe, which might for exemplarypurposes be an area within the building or grounds where they reside,they may optionally be notified with a voice message, tone, vibration orother gentle reminder that they are wandering astray. This movement isillustrated in FIG. 2 as movement from location B to location C.

At the same time, portable location tracking device 120 is preferablyconfigured to provide a short burst transmission containing the Lat-Lonposition offsets to at least one monitoring apparatus 130. This providesimmediate notification to family or medical staff that the person hasleft the safe zone. If the person were to continue to the second alertzone or beyond, other alarms or notifications may be generated by eitheror both of portable location tracking device 120 and at least onemonitoring apparatus 130.

If the person then returns to the safe zone at location D, then portablelocation tracking device 120 may once more communicate with at least onemonitoring apparatus 130 with the offset information, which can then beused within monitoring apparatus 130 to update both status and location.

As may be apparent, the preferred embodiment wireless location assistedzone guidance system 100 is similarly applicable to use within a fencedor even unfenced yard, for a child in a cart at the market, at the park,at the local soccer field, for the walk home from school, or even whenvisiting friends out of town. In any of these situations, a parent,guardian, or staff will be immediately be notified if the monitoredperson wanders outside the safe zone.

The preferred embodiment wireless location assisted zone guidance system100 is also very applicable to use by capable persons. A person runningalone on a predetermined route and carrying self-contained portablelocation tracking device 120 will be notified should they make a wrongturn. In addition, a loved one or friend will immediately be notified aswell through monitoring apparatus 130.

Other embodiments of the invention are applicable to and may becustomized for other animate and inanimate objects, including but notlimited to livestock, pets, wild game, or other animals, machinery, andother diverse apparatus.

Preferred embodiment wireless location assisted zone guidance system 100is illustrated as having a safe zone and three subsequent progressivealert zones. Nevertheless, the present invention is not solely limitedto a particular number of zones within an assisted guidance region, or aparticular way to represent those zones. The numerical representationsfrom zero to three are preferred, but any other representations that maybe machine stored are contemplated herein.

While the preferred embodiment table 10 has been described herein aboveand illustrated in FIGS. 1-3 for the purposes of enablement ascooperative with a particular self-contained apparatus, it should beapparent that the table 10 incorporating discrete values representativeof various zones may be used with other apparatus such as found in manyother patents incorporated herein by reference above and other systems,as will be understood and appreciated by those skilled in the art.

While the foregoing details what is felt to be the preferred embodimentof the invention, no material limitations to the scope of the claimedinvention are intended. Further, features and design alternatives thatwould be obvious to one of ordinary skill in the art are considered tobe incorporated herein. The scope of the invention is set forth andparticularly described in the claims herein below.

I claim:
 1. In combination, a portable location tracking device and amonitoring apparatus, said portable location tracking device having: aGPS location determination apparatus configured to determine aninstantaneous latitude-longitude location of said portable locationtracking device; memory containing a two-dimensional data arraycorresponding to longitude and latitude; a secret reference point withinsaid two-dimensional array that is privately shared with said monitoringapparatus; and a data exchange apparatus configured to transmit anoffset between said instantaneous latitude-longitude location of saidportable location tracking device and said secret reference point; saidmonitoring apparatus having: a data exchange apparatus configured toreceive said offset between said instantaneous latitude-longitudelocation of said portable location tracking device and said secretreference point from said portable location tracking device dataexchange apparatus; and memory containing a two-dimensional data arraycorresponding to said portable location tracking device two-dimensionalarray, and said privately shared reference point within said monitoringapparatus two-dimensional array corresponding to said portable locationtracking device secret reference point; said monitoring apparatusconfigured to apply said received offset between said instantaneouslatitude-longitude location of said portable location tracking deviceand said secret reference point to said privately shared reference pointwithin said monitoring apparatus two-dimensional array and therebydetermine said instantaneous latitude-longitude location of saidportable location tracking device.
 2. The combination portable locationtracking device and monitoring apparatus of claim 1, wherein saidportable location tracking device further comprises: at least onebehavioral guidance stimulation apparatus; a processor; and a pluralityof guidance zones defined using said latitude and longitude information,each one of said plurality of guidance zones having an associated uniqueset of characteristics used by said processor to provide behavioralguidance stimulation through said behavioral guidance stimulationapparatus; wherein each data value stored in said data table identifiesa one of said plurality of guidance zones.
 3. The combination portablelocation tracking device and monitoring apparatus of claim 1, whereinsaid data exchange apparatus is configured to add data noise to saidoffset transmission and thereby further obfuscate said instantaneouslatitude-longitude location of said portable location tracking devicewithin said transmission.
 4. The combination portable location trackingdevice and monitoring apparatus of claim 3, wherein said added datanoise further comprises data resulting from the application of anencryption algorithm to said offset between said instantaneouslatitude-longitude location of said portable location tracking deviceand said secret reference point.
 5. The combination portable locationtracking device and monitoring apparatus of claim 3, wherein said addeddata noise further comprises pseudo-randomly generated data fill.
 6. Thecombination portable location tracking device and monitoring apparatusof claim 1, wherein said secret reference point and privately sharedreference point are both altered subsequent to at least one datatransmission from said portable location tracking device data exchangeapparatus to said monitoring apparatus data exchange apparatus.
 7. Amethod of securely transmitting an instantaneous location of a portablelocation tracking device to a monitoring apparatus, comprising the stepsof: generating a two-dimensional data array representing longitude andlatitude within each of said portable location tracking device and saidmonitoring apparatus; storing a privately held reference point withinsaid generated two-dimensional data array into each of said portablelocation tracking device and said monitoring apparatus; transmitting anoffset between a data table representation of an instantaneous locationof a portable location tracking device and said privately held referencepoint to said monitoring apparatus; applying said transmitted offset tosaid monitoring apparatus two-dimensional data array reference point tolocate said data table representation of an instantaneous location ofsaid portable location tracking device.
 8. The method of securelytransmitting an instantaneous location of a portable location trackingdevice to a monitoring apparatus of claim 7, further comprising thesteps of: storing a value at each individual two-dimensional data arraylocation representing a single behavioral guidance zone selected from aplurality of distinct behavioral guidance zones; storing a unique set ofbehavioral processes associated with each one of said plurality ofdistinct behavioral guidance zones in electronically accessible memory;electronically retrieving said stored value representing said singlebehavioral guidance zone from an individual array location defined bysaid latitudinal offset and said longitudinal offset; and electronicallyretrieving said unique set of behavioral processes associated with saidstored value.
 9. The method of securely transmitting an instantaneouslocation of a portable location tracking device to a monitoringapparatus of claim 7, further comprising the step of adding data noiseto said offset transmission and thereby further obfuscate saidinstantaneous location of said portable location tracking device withinsaid transmission.
 10. The method of securely transmitting aninstantaneous location of a portable location tracking device to amonitoring apparatus of claim 9, wherein said step of adding data noiseto said offset transmission comprises applying an encryption algorithmto said offset between said data table representation of aninstantaneous location of said portable location tracking device andsaid privately held reference point.
 11. The method of securelytransmitting an instantaneous location of a portable location trackingdevice to a monitoring apparatus of claim 9, wherein said step of addingdata noise to said offset transmission comprises adding pseudo-randomlygenerated data fill.
 12. The method of securely transmitting aninstantaneous location of a portable location tracking device to amonitoring apparatus of claim 9, wherein said step of adding data noiseto said offset transmission comprises altering said privately heldreference points subsequent to at least one transmission of said offsetfrom said portable location tracking device to said monitoringapparatus.